数学题求救！！

1.-2a(x-3)^2+8a

2.1/4x+x^3-x^2

3.-m^5n^5+8m^3n^3-16mn

4.4x^2+3y-3xy-4x

5.-(a^2-b^2)^2+2(a^2+b^2)(a+b)^2

.-2a(x-3)^2+8a=-2a(x²-6x+9-4)=-2a(x²-6x+5)=-2a(x-5)(x-1)

1/4x+x^3-x^2=x(x²-x+1/4)=x(x-1/2)²

.-m^5n^5+8m^3n^3-16mn=-mn(m^4n^4-8m²n²+16)=-mn(m²n²-4)²=-mn(mn+2)²(mn-2)²

4x^2+3y-3xy-4x=4x(x-1)-3y(x-1)=(x-1)(4x-3y)

-(a^2-b^2)^2+2(a^2+b^2)(a+b)^2=-(a+b)²(a-b)²+2(a²+b²)(a+b)²=(a+b)²[-(a-b)²+2(a²+b²)]

=(a+b)²(a²+2ab+b²)=(a+b)²(a+b)²=(a+b)^4